How to Select Cows / or, The Guenon system simplified, explained, and practically applied

by Willis P. Hazard

Again, he asks, “how is it that the ramification of the arterial circulation causes the hair to grow in one direction on one part of the cow’s body, and in the opposite on other parts?” Not a very difficult question, if we admit that arteries have such an effect, for they certainly do not all ramify in the same direction.

In a revised edition of the essay, subsequently published, some important points were added. Here we are told that “the arteries supplying the udder with blood are called the mammary arteries, and their ramification does not extend beyond the outer surface of the udder. Further down the aorta, or main artery, another pair of arteries branches off, called the femoral arteries. These supply the muscles of the thigh, or what we know as the rounds of beef, with blood, and ramify upon the portion of the escutcheon lying between them. Still further down, another pair of arteries, called the gluteal arteries, leave the aorta, and are distributed through the pelvic region, and ramify upon the extreme upper portion of the escutcheon. Here we have at least three distinct systems of arteries ramifying upon the escutcheon, and two of them most certainly have no connection with the milk secretion whatever.”

Without attempting to point out all the errors of this description, we will once more refer to Chauveau to settle the more important points. The reader will find in that work that the femoral arteries have a branch called the pre-pubic, which in turn has a branch called the external pudic, from which the mammary artery branches. It will also be found that the mammary artery “sends several divisions to the tissue of the udder, and is prolonged between the thighs by a perineal branch, which terminates in the inferior commissure of the vulva, after having furnished glandular and cutaneous divisions.” Turning to the description of the gluteal arteries, we find that they ramify in the gluteal muscles, which are at a considerable distance from the perineum, and that nothing is said of their going to the last named part.

Here, then, is complete and positive refutation of these arguments—not by mere statements of my own, but by the words of a standard work, of world-wide reputation, on the anatomy of these animals. Magne’s facts are correct, then, whether his inferences are or not. The same artery that supplies the udder with blood supplies the skin on which the escutcheon is formed; and, more than this, the artery ramifies in the direction in which the hair of the escutcheon grows. Is there any connection between the two for all that? Who knows? A point or two to show that such a connection is not beyond the possible may still be in place.

Erasmus Wilson, who has made a specialty of the skin and its diseases, shows that the direction of the hairs on the anterior surface of the human body is, commencing at a point near the arm-pit, downwards and slightly inwards towards the umbilicus, and that below this point the direction is upwards and inwards; so that the umbilicus “is the center of convergence of four streams,” as he expresses it.

Now this disposition, complicated though it is, certainly resembles that of the arteries—the branches from the axillary artery passing downwards and inwards, while the epigastric arteries branch from the femorals near the groin, and have a direction upwards and inwards. On the neck, the direction of the hair is upwards and backwards; in front of the ear, it is downwards and forwards; behind the ear, it is backwards—in each case following the arterial ramifications. In addition, Tisserant and others in France, who stand high as authorities, admit that the escutcheon continues to increase in relative surface till the second or third milking—that is, till the development of the udder, and, consequently, of the vessels supplying it have reached their highest point.

In some cases, it must be confessed, the correspondence in question apparently does not exist, but rather the opposite; and as the mammary artery has substantially the same distribution with horses as with cattle, we cannot see why the former should not be as plainly marked as the latter, if the direction of the hair depends on the direction of the arteries.

But, it may be asked, in what possible manner could the one condition influence the other? It must be remembered that physiology is still a growing science, and that there are many things yet to learn, so that it is still pardonable to confess ignorance. We know, however, that the cavity in the skin surrounding the hair (hair follicle) is set in an oblique direction, as well as the hair that emerges from it; the papilla at the bottom of this cavity must also be inclined, and it is this that, in all probability, decides the direction of the hair, as the growth of this takes place by additions of cells from the surface of the papilla. Now, each papilla, or elevation, has a vascular loop, or, as some say, a minute artery and vein, and one can easily imagine how the direction of this minute artery might influence the direction of the papillary summit, and, consequently, of the hair that grows from it.

I do not say that this is the proper explanation, but I suggest it as one way in which the correspondence might be accounted for. I do say, however, that the evidence brought to bear on this point by Mr. Reeder can have no influence in deciding the question, for the reason I have given.